A former British Gas executive is among a slate of new board members being lined up to scrutinise the Brexit Secretary, David Davis, ahead of the UK’s departure from the European Union (EU).

Sky News understands that Susan Hooper, who sits on the boards of WizzAir and Rank Group, the casino operator, will be named as a non-executive director of the Department for Exiting the EU (DExEU) in the next few weeks.

The appointments will be aimed at strengthening the governance of the Department as negotiations over the terms of Brexit begin to take shape over the coming months.

Theresa May, the Prime Minister, has sought to defuse tensions over whether Britain is heading for a 'hard Brexit' amid a row over the validity of ministerial pronouncements that no deal with the EU would be better than a bad deal.

At least one other new board member is expected to be named alongside Ms Hooper, whose other executive roles included running the Saga cruises and holidays business.

The DExEU appointments follow the recruitment of dozens of figures from the private sector into Whitehall board roles since 2010, following an initiative originally led by Lord Browne, the former boss of BP.

The influx of business expertise was supposed to make Government departments more efficient, although the overhaul is said to have had mixed results.

Among the prominent individuals to have joined Whitehall boards is Archie Norman, the former ITV chairman, who is now the lead independent director at the Department for Business, Energy and Industrial Strategy.